2 player games you can play online with a friend, for free
Most of the time when two people want to play something online, one of them is ready and the other is stuck on a sign-up screen. That's the bit I care about here.
So this is a short list of free two-player games that run in a browser. For each one I've noted the thing that usually trips people up: what your friend has to do before the game starts.
I make one of these games, so I'm not neutral. BattleTabs is on the list, and I've tried to be fair to the others anyway.
Chess on Lichess
If you both know chess, start here. Lichess calls itself a free, open-source chess server with "no registration, no ads, no plugin required", and it's run by volunteers and funded by donations.
To play someone you know, there's a "Play with a friend" button on the home page that makes a game and gives you a link to send. A heads-up from the Lichess forum: that link is a game between you and whoever opens it first, so send it to one person, not a group chat.
Chess on Chess.com
Chess.com has a play-a-friend page and playing a friend there is free. The catch is that both of you need an account. People on the Chess.com forum found the challenge link asks a new player to register first.
If your friend already plays there, use it. If they don't, Lichess gets you to the first move faster.
Board Game Arena
This is the one to bookmark if you like board games more than chess. Board Game Arena says it has more than 1,400 games, it's free to join, and it runs in the browser with no download.
You can send a friend an invitation link to your table, and BGA's own news post says that works even if they don't have an account yet. There is a paid Premium membership on top. Some games and features sit behind it, so check the game page before you promise your friend a particular one.
Pen and paper, over a call
It's easy to forget this one. Plenty of two-player games only need a grid you can both draw and a way to talk.
Battleship started out this way. According to its Wikipedia history, people played it on paper before World War I, and the plastic pegboard version only arrived in 1967. Draw two 10×10 grids each, call out your shots over the phone, and you're playing.
It's slow, and somebody always forgets to mark a miss. No accounts, though.
BattleTabs
BattleTabs is a turn-based sea battle, a bit like Battleship. You each have four ships and try to sink the other fleet first. The twist is that ships have special abilities on a cooldown. Some scout and some hit several squares at once, so you spend more time outthinking your friend than guessing.
For playing with a friend, you start a friendly battle and either invite a friend or share a link. On desktop it runs in the browser with nothing to install. On a phone, your friend gets it from the App Store or Google Play. It's free, and it's also free-to-play on Steam.
If they turn out to like it, every account has a Friend Code too, so you can add each other once and find the next game without another link.
If you're new to it, play Battleship online free covers what a match looks like. This old post is where battle links first showed up, back in 2021. And if you want to beat your friend the first time, my Battleship strategy post on placement and first shots mostly carries over.
Picking one
If you both play chess, Lichess. If you want variety and don't mind poking around, Board Game Arena. If you want something quick you can both start in a minute, I'd obviously like you to try BattleTabs.